bluecape, how goes it! been wondering along similar lines. i think the answer might be a bit of both, that breath hold training can increase your real bottom time(ie push back the point of blackout), and at the same time also increase your comfort faze (without extending you final b/o point). pure CO2 tolerence training might do mostly the latter, whereas pure O2 tolerence training might do more pf the former. by this thinking i am moving away from from apnea walks and max statics to pure hypoxia training (empty lung tables done with much hyperventilating). as with the FVC/empty lung freedivers, i'm gambling on some real returns as the body adapts to constant hypoxia. the returns from hypercapnia training are much easier/quicker to come by but of questionable importance to anyone other than a static apniest i recon. hope this thread keeps alive till one of the 'experts' puts it to sleep. chow
bevan
bevan